Pressure apparatus



Nov. 3, 1964 D. c. GREEN 3,155,041

PRESSURE APPARATUS Filed. May 16, less 2 sheets-sheet 1 r" I B 37 6% I 0 67 35 es 0 I 2738 62 .:.::.L, 3 a4 F5 33 34 INVENTOR.

His Aft orngu Nov. 3, 1964 D. c. GREEN 3,155,041

PRESSURE APPARATUS Filed May 16. 1963 2 Sheets-Sheet 2 I NVEN TOR. Dana/0 C. Green United States Patent O 3,155,041 PRESSURE APPARATUS Donald C. Green, Russell Township, Geauga County, Ohio, assignor to Mansfield-Green, lino, Solon, Ohio, a corporation of Ghio Filed May 16, 1963, Ser. No. 291,593 4 Claims. ((Il. 103-37) This invention relates to pressure apparatus, more particularly to portable apparatus for actuating and testing pressure responsive mechanical devices, equipment, and including pressure indicating guages. This is a continuation-in-part of application Serial Number 120,683, filed June 29, 1961, now abandoned.

In the area of pressure actuation of mechanical ele ments such as testing of diaphragms, guages, seals, and pressure containers, pumps, either hand or motor operated, generally forward fixed volumes of the pressure fluid, oil or water, to the point or area being pressure actuated, fixed volume pumps are ordinarily utilized and such pump comprises a single cylinder or plunger pump of predetermined diameter and a lever arm for providing the necessary force to forward the pressure fiuid and to reach a desired predetermined value. Where it is desired to reach a value beyond that for which the pump was designed the required force becomes increasingly greater in demand and an extra means, as a gear box, or lever arm extension to provide for greater force, has to be utilized. The extra required pressure while obtained, means not only extra equipment in the provision of longer lever arms, or of reduction gearing where motors are used but, also, the pressure pump itself is endangered because it is not generally designed for additionally higher pressures.

Further, single cylinder pressure pumps are not flexible in the sense that an extended pressure range cannot be readily had. Once a maximum design pressure reading is reached anything beyond such reading is not only difiicult to obtain without substantial supplemental force but the pump design is generally not capable or" withstanding the extra pressure. Generally, then, there is required a separately designed pump for each pressure test point. It would be advantageous to combine into a single pump one providing for at least two or more pressure ranges without the requirement of an additionally great force beyond that normally required to operate a unit pump.

Advantageously the aforesaid principle is embodied in the improved pump of this invention. From an enlarge fixed volume of a pressure fluid there is subsequently subtracted, by predetermined increments, volumes permitting continued use of substantially normal force to enable an operator to reach a higher range quickly. The smaller incremental volumes are then forwarded under normal force requirements readily attaining the further second or third range pressures. The change in the volume of pressure liquid is effected by an elimination or recirculation of one or more of the volumes back into the pump reservoir meanwhile working with only the remaining incremental additional volumes. This is achieved by rendering ineffective a portion of the cylinder area leaving a diminished one on which to apply a generally normal force to reach a higher pressure range otherwise not available.

As stated the change in pressure volumes is attained through a change in the areas of the pump cylinder or plunger. The cylinder or plunger comprises a unit having different diameters in a stepwise relation. The total pressure liquid volume is equal to the total cross-sectional area of the plunger or cylinder and its stroke length. By by-passing the volume of one or" the areas of the two or more diameter plungers a reduced volume is acted on 'ice requiring a force determined by the new conditions.

The invention will be readily understood from the following description in connection with the accompanying drawing, where:

FIGURE 1 represents, diagrammatically, one form of a liquid pressure testing pump unit;

FIGURE 2 shows in partial section and plan view a two-diameter pump, plunger, and piping to a test unit;

FIGURE 3 shows a two diameter pump unit of the type of FIGURE 2 with the plunger in withdrawn position;

FIGURE 4 represents, as a bottom View, the concentric plunger area of FIGURES 2 and 3 that is capable of being utilized;

FIGURES 5 and 6 represent in plan and bottom views a further variation of pump and plunger diameters;

FIGURE 7 represents in plan and partial section a further variation in pump plunger diameter;

FIGURES 8 and 9 represent a further modification of the pump unit; and

FIGURE 10 represents, in partial section, a modified fluid pressure check valve.

As shown in FIGURE 1 a pressure testing pump may conveniently take the form of a unit portable apparatus adapted to be carried to the area where pressure tests are to be performed. The unit 12 of FIGURE 1 may be secured to a base it providing for stability during use. The base ll may desirably form one part or" a carrying case or cover (not shown) when stored or for transport, the test conduit for supporting test instruments being first removed. The pumping unit 12 consists of a reservoir it) for a pressure liquid (oil or water) and an attached pump 13 which is actuated'by a handle or lever 15 pivoted at 17 and attached to a connection 16 of the pump plunger shown in the subsequent views of the remaining figures. To the pump 13 outlet there is connected a pipe or conduit support 1d adapted to hold guages Zii, 2-1 in each of its extensions, the one being tested against the other. a

The pump unit of FIGURE 1 ditlers over standard types in that it has greater flexibility because of the pump construction and of the pumping plunger or cylinder. Referring to FIGURES 2 and 4 the plunger 25 and housing 24 have two diameters; of the two section as is the larger and 27 is the smaller. in effect the plunger 25 is formed stepwise of two varying diameter pistons. The plunger 25 moves in the housing 24- having chambers conforming substantially to the diameters of the plunger sections 26, 27. The plunger 25 is operated through an extension 2% attached to the pump arm 36? which is desir ably pivoted at 31, for leverage, on the pump housing 24. When the plunger 25 is raised there are created two volumes, that by the displaced plunger section 26 and section 27. These volumes may be combined or one may be by-passed in the operation of the pump.

The section of the pump housing 24 containing the larger diameter cylinder or plunger section 26 and the lower housing section containing lesser plunger section 27 are each connected to a reservoir supply of pressure liquid. A conduit 33 through modified check valve 34 admits or exhausts a pressure liquid to each of the aforesaid; the talre-otl conduit 35 being connected to the upper or larger volume chamber while the main conduit 33 is connected to the lower or lesser volume chamber. The take-off conduit 35 also includes a modified one-way control valve 36. The pressure liquid from within the volume chambers is forced out through the exhaust conduit 37, including a modified check valve 33 to the pipe support 4% thence to the instruments tested, 41, 42. The valves 34, 36 and 38 are one-way valves under normal pumping operation to hold the pressure liquid forced beyond them, however, for exhaust or by-pass purposes 2% they can be and are manually operable, as shown in FIG- URE 10, to release any built-up pressure by returning the liquid to the reservoir.

The volumes created by the raising of the plunger, when subjected to pressure by the combined plunger area, are forced into outlet conduit 37. When a greater pumping force is obviously demanded to reach a higher desired pressure value, as evidenced by an increase in pumping resistance which it is desired to overcome, the valve 34 in the supply line may be opened and the volume of the lower chamber by-passed to the reservoir while the decreased volume of only the upper volume chamber is acted upon; thus reducing or eliminating that force that would have been required over and above the initial conditions.

This is shown more clearly in FIGURE 3. When the pump plunger 45 is raised within housing 44 the movement creates volume chambers occupied by cylindrical plunger sections 46 and 47. These are at once filled with liquid through the conduit 49, through the modified oneway valve 50, take-elf conduit 51, and modified check valve 52. This combined volume is then forced out of both chambers, that from the lower housing volume chamber 48 passing through the upper volume chamber, into outlet 54,, through modified check valve 55, to a pressure point. In operation the plunger 45 is forced down the liquid is prevented from flowing back to the reservoir by the valve 50 in the feed line and thus can only go one way, through the upper housing volume chamber, into outlet 54. Where the pumping pressure begins to increase noticeably while pumping through both volumes the pressure can be kept at a lower value by bypassing the lower volume to the reservoir through manipulation of the valve 50, leaving the larger plunger pumping area in efiect and thus a lower or normal force requirement.

Where a double-test range is not too far apart but the upper range is sensitive of attainment a plunger of different diameters is desirable. The difference, however, should only be such so as to provide for an incremental volume needed to quickly reach the pressure point. To satisfy such a need the plunger may take the form shown in FIGURES 5 and 6. As shown, the plunger 66 is of two diameter sections 61, 62. Section 62 is the smaller to an extent equivalent to an area providing for a greatly diminished volume of liquid. The remaining small volume is then pumped under a lesser force acting only on the area difference between 61 and 6.2 section, and a slower readily reachable approach to the pressure point is attained. Here a liquid supply conduit 63 provides pressure liquid through modified check valve 64, take-oil 65, and modified check valve as to the pump. The liquid is exhausted or forced out through outlet 67 and the modified check valve 63 therein to a pressure station.

Further, where there is an appreciable spread between pressure ranges as, for instance, from 12,000 lbs. to 13,000 lbs. and perhaps higher the plunger diameter differences are desirably made greater. The entire plunger area generally is utilized until resistance is felt indicating an approach to the lower of two ranges then as the pumping requires greater force the larger of the two volumes is bypassed to the reservoir and the smaller is pumped by a smaller plunger area thus more slowly building up the pressure incrementally. Such a pump unit is shown in FIGURE 7. The plunger piston 7b is formed of two sections, the upper section '71 being a number of times the size of the lower section '73. Liquid is supplied from a reservoir (not shown) through conduit '76 and modified check valve 77 to lower housing volume chamber 7% through modified check valve 73. It is supplied to the upper housing chamber volume 75 through the take-off conduit 79 and modified check valve 83. On a down stroke the liquid is forced from volume chamber 75 into exhaust outlet 33 and through modified check valves 84, $6 to a test support (not shown). An outlet 82 is also provided for the lower volume chamber 74. It coni nects with the upper outlet 83 beyond valve 84 and thence with the test support (not shown). Initially the total volume is pumped until resistance is felt requiring an additional pumping force to overcome it. As stated hereinbefore this resistance can very well be the lower of the two pressure ranges. To get the higher range without substantial additional force the higher volume from chamber is by-passed to the reservoir by manipulating the valve 77 and 80, while only chamber 74 is continually supplied with a pressure liquid. Modified check valve 78, being uni-directional, will prevent losses while admitting a liquid. The liquid from chamber 74 is pumped out into utlet 82 thence into conduit 83. It cannot go into-chamber 75 because of the normally uni-directional valve 84 in the outlet conduit 83. The volume '74 being small requires a greatly reduced force to act on it yet permitting high pressures to be reached easily, incrementally.

A further variation in the construction of the pump plunger can provide for still more testing flexibility giving a wider and a higher range. The plunger can be constructed of at least three cylindrical sections of different diameters. Substantial pressures can be attained by a subsequent sequential elimination of working areas of the plunger so that generally normal forces can be conttnually applied. In FIGURES 8 and 9 the plunger 94 positioned in housing 9%) is formed in three sections 95, 96 and 97 of step-wise diminishing diameters. Each occupies a volume chamber into which a liquid is admitted and expelled. Conduit 100 supplies a liquid from a reservoir through modified check valve ltll to the lowest volume chamber and take-0E conduits 192 and 104, in which are positioned modified check valves 103 and Th5, connect with and supply the intermediate and top volume chambers in housing 9%. Liquid from each of the lower two chambers is added to that of top volume chamber, and when the plunger is lowered the sum total is forced out of the housing through outlet 106 and modified check valve W7.

Valves herein referred to as being normally uni-directional or as modified check valves are check valves of the type shown in FIGURE 2 of the patent to Green, No. 2,481,482, or FIGURE 1 of the improvement patent to Green, No. 2,912,001. As shown in FIGURE 10 of the drawing, the modified valve casing 116 is suitably bored to receive a desirably sealed shaft 111 having an operating handle 117.. A cam 113 is mounted on the shaft 112 to lift the plug 114 and prevent operationof the valve as a check valve. This provides for by-passing of certain desired pressures and permits dumping of pressure from the stands 19 and id.

From the aforesaid description it can be seen that bypasses can be provided with proper valving so that any of the volumes or a combination of them can be selected for forwarding. The selection being dependent on a desirable maintenance of normal working forces on the pump. Also, more than one testing range can be reached readily through such selections thus making one testing unit replace several individual units. And because a plunger portion or section can be made almost infinitesimally small giving smaller working areas very high pressures can be readily reached.

What is claimed is:

l. A pressure pump apparatus comprising, a closed circuit for circulation of a pressure fluid, a reservoir of pressure fluid, a pump joined to said reservo ir for forwarding said pressure fluid to a pressure point subject to testing, a pumping plunger in said pump having stepwise decreasing diameters, a pump housing conforming to said plunger, access and exit conduits to each stepwise section of said housing, an outlet conduit connected to said pump for conducting the combined flows from each of said sections as a unit enlarged volume to said pressure point, a modified check valve in each access conduit, a modified check valve in the outlet conduit, means for manipulating desired modified check valves to bypass desired pressures to other pump sections.

2. A pressure pump apparatus comprising, a closed circu-it for circulation of a pressure fluid, a reservoir of pressure fluid, a pump joined to said reservoir for forwarding said pressure fiuid to a pressure point subject to testing, a pumping plunger in said pump having stepwise decreasing diameters, a pump housing conforming to said plunger, access and exit conduits to each stepwise section of said housing, an outlet conduit connected to said pump for conducting the combined flows from each of said sections as a unit enlarged volume to said pressure point, a modified check valve in each access conduit, a modified check valve in the outlet conduit, means for manipulating desired modified check valves to by-pass desired pressures to other pump sections to said reservoir.

3. A pressure testing pump comprising, a reservoir of pressure liquid, a pump for forwarding said liquid to a pressure test point, a main passage from said reservoir to said pump, a unitary plunger in said pump having at least two stepwise different diameters providing for at least two difierent volume pumps, a pump housing conforming to the different sizes of said plunger to form separate pumping chambers, a separate passage joining said main liquid passage to each of said pumping chambers, valves in said passages for permitting in and out liquid flow to each of the pumping chambers, separate outlet passages from said pumping chambers subsequently joining to provide a common pressure passage to a pressure point, a normally uni-directional valve in one of said outlet passages for preventing back-flow therethrough, and a normally uni-directional valve in the common outlet pressure passage for securing the pressure value reached, certain of said normally uni-directional valves being manually opened whereby liquid under pressure from a test point may flow back to the reservoir.

4. A pressure testing pump comprising, a reservoir of pressure liquid, a pump for forwarding said liquid to a pressure test point, a main passage from said reservoir to said pump, a unitary plunger in said pump having at least two stepwise different diameters providing for at least two different volume pumps, a pump housing conforming to the different sizes of said plunger to form separate pumping chambers, a separate passage joining said main liquid passage to each of said pumping chambers, valves in said passages for permitting in and out liquid flow to the pumping chambers, separate outlet passages from said pumping chambers subsequently joining to provide a common passage to a pressure point, a normally unidirectional valve in both the inlet and outlet passage to the larger of two pumping chambers preventing flow therethrough and limiting the pump output to the lesser, and a normally uni-directional valve in the common outlet passage for securing the test pressure value reached, said last named valve being manually opened whereby liquid under pressure from a test point may flow back to the reservoir.

References Cited in the file of this patent UNITED STATES PATENTS 617,135 Weeks Ian. 3, 1899 833,457 Hammond Oct, 16, 1906 867,932 Weeks Oct. 8, 1907 1,904,531 Raymond Apr. 18, 1933 2,255,984 Pfanser Sept. 16, 1941 2,439,796 Dearsley Apr. 20, 1948 2,442,058 Page May 25, 1948 2,688,231 Northcutt Sept. 7, 1954 2,922,373 Pahl Jan. 26, 1960 2,989,001 Wilkenlok et al June 20, 1961 FOREIGN PATENTS 656,076 France Dec. 24, 1928 

1. A PRESSURE PUMP APPARATUS COMPRISING, CLOSED CIRCUIT FOR CIRCULATION OF A PRESSURE FLUID, A RESERVOIR OF PRESSURE FLUID, A PUMP JOINED TO SAID RESERVOIR FOR FORWARDING SAID PRESSURE FLUID TO A PRESSURE POINT SUBJECT TO TESTING, A PUMPING PLUNGER IN SAID PUMP HAVING STEPWISE DECREASING DIAMETERS, A PUMP HOUSING CONFORMING TO SAID PLUNGER, ACCESS AND EXIT CONDUITS TO EACH STEPWISE SECTION OF SAID HOUSING, AN OUTLET CONDUIT CONNECTED TO SAID PUMP FOR CONDUCTING THE COMBINED FLOWS FROM EACH OF SAID SECTIONS AS A UNIT ENLARGED VOLUME TO SAID PRESSURE POINT, A MODIFIED CHECK VALVE IN EACH ACCESS CONDUIT, A MODIFIED CHECK VALVE IN THE OUTLET CONDUIT, MEANS FOR MANIPULATING DESIRED MODIFIED CHECK VALVES TO BY-PASS DESIRED PRESSURES TO OTHER PUMP SECTIONS. 